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Uses Little's Law to calculate the target queue size to achieve a target waiting time as a function of observed demand, target wait and a variability factor used in the target mean waiting time calculation.

Target Queue Size = Demand * Target Wait / 4.

The average wait should sit somewhere between target_wait/factor=6 < Average Waiting Time < target_wait/factor=4 The factor defaults to 4.

Only applicable when Capacity > Demand.

Usage

calc_target_queue_size(demand, target_wait, factor = 4)

Arguments

demand

Numeric value of rate of demand in same units as target wait e.g. if target wait is weeks, then demand in units of patients/week.

target_wait

Numeric value of number of weeks that has been set as the target within which the patient should be seen.

factor

Numeric factor used in average wait calculation

  • to get a quarter of the target use factor=4

  • to get one sixth of the target use factor = 6 etc. Defaults to 4.

Value

Numeric target queue length.

Examples

# If demand is 30 patients per week and the target wait is 52 weeks, then the
# Target queue size = 30 * 52/4 = 390 patients.

calc_target_queue_size(30, 52, 4)
#> [1] 390